Traffic will be temporarily reconfigured as a right-in-right-out intersection during closure for CO 119 Project

Boulder County, Colo. - As a part of the CO 119 Safety, Mobility and Bikeway Improvements Project, the Niwot Road median between northbound and southbound Colorado Highway 119/Diagonal Highway will be closed to all modes of transportation beginning Wednesday, March 25, at 7 p.m. to Monday, March 30, at 5 a.m.

During these closures, Niwot Road and CO 119/Diagonal Highway will be configured as a right-in-right-out intersection. There will not be a separate signed detour in place for cyclists. Cyclists are encouraged to use an alternate route while the closures are in place.

These closures are required for crews to complete signal work, final alignment striping, concrete paving operations and guardrail installation.

Motorist detour:

• Westbound Niwot Road travelers will turn right onto northbound CO 119/Diagonal Highway, exit and turn left onto Airport Road, and turn left back onto southbound CO 119/Diagonal Highway to return to Niwot Road.
• Eastbound Niwot Road travelers will turn right onto southbound CO 119/Diagonal Highway, turn left onto Colorado Highway 52 and left onto northbound CO 119/Diagonal Highway to return to Niwot Road.

During the closure, the RTD bus stop on southbound CO 119 at Niwot Road (stop #18095) will be closed. The bus stop closure is required for the safety of the traveling public and project crews. Riders are advised to use the bus stop on southbound CO 119 at Monarch Road (stop #24826) during this time.

Niwot Road closure detour map.

To complete construction work at the Niwot Road median with minimal impacts to travelers, the project team decided to close the median entirely for approximately five days. The alternative would be continuously shifting barriers and traffic flow around the operations for multiple weeks, extending the duration of the overall impacts to the Niwot Road and CO 119 intersection for all roadway users.

Work schedules are subject to change and can vary based on conditions. Subscribe to CO 119 Diagonal Highway Safety, Mobility and Bikeway Project Construction Updates from CDOT.

View the CDOT CO 119 Safety, Mobility & Bikeway page for more construction updates.

Project Contacts

• CDOT phone: 720-378-8083
• CDOT email: co119safetyandmobility@gmail.com
• Boulder County phone: 303-441-4520
• Boulder County email: aphillips@bouldercounty.gov

Boulder County wants to ensure that everyone has equal access to our programs, activities, and services. To request an Americans with Disability Act (ADA) accommodation, please email ada@bouldercounty.gov, or call 303-441-1386. If you need help in another language, please email cppfrontdesk@bouldercounty.gov or call 303-441-3930.